Preparation of Chromatographic Media from Algerian Diatomite

Abstract

X-ray photoelectron spectrometry combined with FTIR spectroscopy, X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM) allowed highlighting the different interactions of grafts or impregnated polymers on the mineral surface of diatomite obtained by treatment of raw diatomite under reflux with a 5 M solution of hydrochloric acid for 24 h. This acid treatment led to almost total elimination of organic impurities with a total decalcification of the diatomite, leading to its deferrization and partial dealumination, and the obtaining of a support with a homogeneous siliceous surface mainly constituted of Si−OH and Si−O−Si functional groups. The surface of the diatomite washed with HCl became totally saturated with PEG-20M and SE30 with respective impregnation rates of 5 and 2 %. However, the grafting and/or impregnation of this diatomite with octadecyltrichlorosilane (C18) and docosane (C22) led to the formation of perfectly homogeneous surfaces.

Keywords

• diatomite
• characterization
• grafting
• impregnation
• x-ray photoelectron spectroscopy (xps)
• surface properties